If it was up to me the Rams would sign OBJ to a contract with very little guaranteed but with incentives that could make the deal something that OBJ could live with. Almost all of the the risk, then would be on OBJ. But if he's willing to bet on himself maybe this is the win-win deal that brings OBJ back to the Rams.
$2M salary guaranteed, $625,000 for each game that he's healthy enough to play in? That's $7M if he's available for 8 games. You want $7M for this season? Get your butt in the field!!
I know we are all hopeful for a mid-November return but I doubt the NFL sees that as likely. Maybe they look at OBJ being 30, this is his second ACL tear in the same knee, and he got hurt on Feb 13 and figure that he doesn't come back until the playoffs at the earliest. If that's the way it plays out the incentives would be determined to be 'not likely to be earned' and the deal would only count $2M against this year's cap.
Any incentives that OBJ would collect would of course be paid as they are earned, but they would count against next year's cap in this scenario.
AlbaNY_Ram